2005 Cadillac STS Owner's Manual - Page 307

When to Add Engine Oil If the oil is below the cross-hatched area at the tip of the dipstick, then you will need to add at least one quart of oil. But you must use the right kind. This section explains what kind of oil to use. For engine oil crankcase capacity, see Capacities and Specifications on page 5-104. Notice: Do not add too much oil. If your engine has so much oil that the oil level gets above the cross-hatched area that shows the proper operating range, your engine could be damaged. What Kind of Engine Oil to Use Look for two things: • GM4718M Your vehicle's engine requires a special oil meeting GM Standard GM4718M. Oils meeting this standard may be identified as synthetic. However, not all synthetic oils will meet this GM standard. You should look for and use only an oil that meets GM Standard GM4718M. Notice: If you use oils that do not have the GM4718M Standard designation, you can cause engine damage not covered by your warranty. 3.6L V6 Engine 4.6L V8 Engine See Engine Compartment Overview on page 5-12 for the location of the engine oil fill cap. Be sure to add enough oil to put the level somewhere in the proper operating range. Push the dipstick all the way back in when you are through. 5-17